Semiconductor devices including dual gate structures that include dual metal electrodes, or gates, on high-K dielectrics are expected to be a basis for the next generation of memory devices. However, reliable manufacturing and integration of dual metal gates having two different work functions has been a challenge. For example, conventional methods of forming dual metal gates having two different work functions requires etching a metal layer over a portion of the high-K dielectric material before applying another metal layer, which may cause etch-induced damage to the high-K dielectric material.
For the reasons stated above and other reasons that will become apparent to those of ordinary skill in the art upon reading and understanding the present specification, there is a need in the art for improved semiconductor devices including dual gate structures and methods of forming such semiconductor devices.